As the Chicago area grappled with a third-straight day of unhealthy air quality levels on Thursday caused by Canadian wildfire smoke, many residents are wondering how smoke from so far away can have such a drastic impact on air quality and visibility.
While the eerie images of a smoke-clouded skyline and days of poor air quality are very unusual for Chicago, the carriage of smoke and other particulates for hundreds or even thousands of miles is fairly common, NBC Chicago meteorologist Kevin Jeanes said.
Although wildfire smoke often stays high in the atmosphere and therefore does not have widespread impacts on air quality, certain wind patterns and conditions can keep the smoke low and thick as it travels for long distances.
Jeanes referenced dust from the Sahara Desert that can travel across the ocean while still impacting visibility and air quality.
Both favorable conditions for the long-distance movement of smoke and a historic wildfire season in Canada has led to widespread air quality issues across much of North America throughout June.
The severe impact to Chicago has been made possible by the location of the Canadian wildfires, with Ontario and Quebec, located north and northeast of Chicago, seeing one of their worst wildfire seasons ever.
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